Building on TE-18.1 and TE-18.2, this test focuses on scaling gRIBI-programmed MPLS-over-UDP tunnels and associated forwarding entries, parameterized by key scaling dimensions.

Physical Topology:

• 4 physical ports total (2 DUT ports + 2 ATE ports)
  • 2 ports as ingress interfaces (port1-port2)
  • 2 ports as egress/uplink interfaces (port3-port4)

Logical Interface Scale Design:

• 32 logical ingress interfaces achieved through:
  • 16 VLAN subinterfaces per physical ingress port (2 ports × 16 VLANs = 32 logical interfaces)
  • VLAN IDs: 100-115 on port1, 200-215 on port2
• Multiple VRFs mapped to logical interfaces as required by scale profiles
• Each logical interface assigned to appropriate VRF based on test profile requirements

ATE port-1 <------> port-1 DUT (VLANs 100-115)
ATE port-2 <------> port-2 DUT (VLANs 200-215)
DUT port-3 <------> port-3 ATE (Egress)
DUT port-4 <------> port-4 ATE (Egress)

• 32 logical interfaces as the ‘input port set’ (Ingress)
• 2 ports as “uplink facing” (Egress)
• Network Instances (VRFs) will be mapped from ingress ports/subinterfaces as needed by scale profiles.

1. Physical Interface Configuration:

   • Configure ports 1-4 with IPv6 addressing using base scheme 2001:f:d:e::/126 network
   • Enable all physical interfaces with PMD100GBASEFR-specific settings
   • Apply ethernet configuration: AutoNegotiate=false, DuplexMode=FULL, PortSpeed=100GB
   • Set MAC addresses using systematic scheme: 02:01:00:00:00:XX for DUT ports

2. VLAN Subinterface Configuration:

   • Create 16 VLAN subinterfaces per ingress port (32 total logical interfaces)
   • Assign IPv6 addresses using 2001:f:d:e::/126 base with systematic increments
   • Configure subinterface-to-VRF mappings based on test profile requirements
   • Enable IPv4 protocols on subinterfaces when deviations.InterfaceEnabled(dut) is required

3. VRF Configuration:

   • Create required VRFs based on test profile:
     • Profile 1: DEFAULT network instance only
     • Profiles 2-3: 1024 VRFs (VRF_001 through VRF_1024) plus DEFAULT
     • Profile 4: DEFAULT network instance only
     • Profile 5: DEFAULT network instance only
   • Use device-specific default network instance naming conventions
   • Apply policy-based forwarding rules for VRF selection using DSCP/source IP criteria

4. Static Routes and Forwarding:

   • Configure static routes using device-specific static protocol naming
   • Set up IPv6 static routes with next-hop pointing to ATE port IPv6 addresses
   • Use standard static route protocol type configuration
   • Configure routes in appropriate network instances based on test profile requirements

1. Physical Port Setup:

   • Configure 4 physical ports with IPv6 addresses matching DUT interface scheme
   • Use MAC addresses: 02:00:XX:01:01:01 pattern for ATE ports
   • Set up VLAN tagging on ingress ports (port1-2) to match DUT subinterface VLANs
   • Configure egress ports (port3-4) for traffic reception and MPLS-in-UDP validation
   • Apply PMD100GBASEFR-specific settings: disable FEC, set speed to 100Gbps, enable auto-negotiate

2. Traffic Generation:

   • Create traffic flows targeting the 20,000 unique destination prefixes
   • Use IPv6 flow destination base: 2015:aa8:: as defined in Test Parameters
   • Distribute traffic across 32 logical ingress interfaces using VLAN tags
   • Configure flows with appropriate DSCP markings for VRF selection
   • Set traffic duration: 15 seconds as defined in Test Parameters

3. Packet Capture and Validation:

   • Enable packet capture on egress ports for MPLS-in-UDP encapsulation validation
   • Configure capture filters for MPLS label stack and UDP encapsulation verification
   • Validate outer IPv6 headers: source 2001:f:a:1::0, destination 2001:f:c:e::1 as defined in Test Parameters
   • Verify UDP destination port 6635 as defined in Test Parameters
   • Check outer DSCP marking: 26 and TTL: 64 as defined in Test Parameters

1. Client Configuration:

   • Establish gRIBI client connection with RIB_AND_FIB_ACK: true and Persistence: true
   • Use standard gRIBI client configuration pattern
   • Make sure the client is the leader
   • Set appropriate batch sizes and operation rates per profile requirements

2. Entry Programming Sequence:

   • Program Next Hop (NH) entries with MPLS-in-UDP encapsulation headers
   • Use NH ID starting from 201 as defined in Test Parameters
   • Create Next Hop Groups (NHGs) starting from ID 10 as defined in Test Parameters
   • Install IPv6 prefix entries using 2015:aa8::/128 base prefix pattern as defined in Test Parameters
   • Validate FIB_PROGRAMMED status for all programmed entries

3. Scale-Specific Configurations:

   • Profile 1: DEFAULT network instance with 20,000 NHGs, 1 NH per NHG, 1 MPLS label
   • Profiles 2-3: 1024 VRFs with distributed NHGs/prefixes, unique MPLS labels per VRF
   • Profile 4: DEFAULT network instance with 2,500 NHGs, 8 NHs per NHG (ECMP), 1 MPLS label
   • Profile 5: High-rate programming (1,000 ops/sec) with 50% ADD/50% DELETE operations

4. Device-Specific Considerations:

   • Handle vendor-specific gRIBI encapsulation header support limitations
   • Use CLI configuration for tunnel encapsulation when gRIBI encap headers unsupported
   • Apply device-specific interface enablement requirements for IPv4 protocols
   • Configure tunnel type: "mpls-over-udp udp destination port 6635" as defined in Test Parameters

DUT Interface IPv6 Addressing:

• dut_port_base_ipv6 = “2001:f:d:e::/126”
• dut_port1_ipv6 = “2001:f:d:e::1/126”
• dut_port2_ipv6 = “2001:f:d:e::5/126”
• dut_port3_ipv6 = “2001:f:d:e::9/126”
• dut_port4_ipv6 = “2001:f:d:e::13/126”

ATE Interface IPv6 Addressing:

• ate_port1_ipv6 = “2001:f:d:e::2/126”
• ate_port2_ipv6 = “2001:f:d:e::6/126”
• ate_port3_ipv6 = “2001:f:d:e::10/126”
• ate_port4_ipv6 = “2001:f:d:e::14/126”

MAC Address Schemes:

• dut_mac_pattern = “02:01:00:00:00:XX”
• ate_mac_pattern = “02:00:XX:01:01:01”

Inner IPv6 Destinations:

• inner_ipv6_dst_A = “2001:aa:bb::1/128”
• inner_ipv6_dst_B = “2001:aa:bb::2/128”

Inner IPv4 Destinations:

• ipv4_inner_dst_A = “10.5.1.1/32”
• ipv4_inner_dst_B = “10.5.1.2/32”

Outer IPv6 Encapsulation:

• outer_ipv6_src = “2001:f:a:1::0”
• outer_ipv6_dst_A = “2001:f:c:e::1”
• outer_ipv6_dst_B = “2001:f:c:e::2”
• outer_ipv6_dst_def = “2001:1:1:1::0”
• outer_dst_udp_port = “5555”
• outer_dscp = “26”
• outer_ip_ttl = “64”

Traffic Flow Parameters:

• ipv6_flow_base = “2015:aa8::”
• ipv6_prefix_base = “2015:aa8::/128”

Traffic Parameters:

• traffic_duration = “15 seconds”
• target_packet_loss = “≤ 1%”

gRIBI Parameters:

• nh_id_start = “201”
• nhg_id_start = “10”

This test evaluates scaling across the following dimensions using gRIBI. The test profiles below represent different parameter combinations of these dimensions.

• Network Instances (VRFs): Number of separate routing instances.
• Next Hop Groups (NHGs): Total number of NHGs programmed. Target: Up to 20,000 (profile-dependent).
• Next Hops (NHs): Total number of NHs programmed. Constraint: Maximum 20,000 total NHs. When there are more NHs per NHG, there will be fewer total NHGs (e.g., 2,500 NHGs if each NHG has 8 NHs).
• NHs per NHG: Number of NH entries within each NHG (e.g., 1 or 8).
• Prefixes: Total number of unique IPv4/IPv6 exact-match forwarding entries (routes) across all VRFs. Target: 20,000 total.
• (Unique Destination IP + MPLS) Tuples: The combination of the inner destination IP and the MPLS label used in the NH encapsulation. Target: Up to 20,000 unique tuples.
• MPLS Labels: Number and uniqueness of MPLS labels used in NH encapsulation. Constraint: The number of unique MPLS labels must equal the number of VRFs (#MPLS Labels == #VRFs).
• gRIBI Operations Rate (QPS): Rate of gRIBI Modify requests or operations per second.
• gRIBI Batch Size: Number of AFT entries (or operations) per ModifyRequest.
• Convergence: DUT packet forwarding updated within 1 second after receiving FIB_PROGRAMMED acknowledgement for added entries (baseline).
• IP Address Reuse: Inner IP destination prefixes should be reused across different Network Instances where applicable.
• Multi-VRF Distribution: In multi-VRF profiles, both NHGs and prefixes are distributed across the different VRFs as specified in each profile.

• Goal: Baseline single VRF scale (Exact Label Match scenario).
• Network Instances (VRFs): 1 (DEFAULT).
• Total NHGs: 20,000.
• NHs per NHG: 1.
• MPLS Labels: 1 (consistent with #VRFs = 1). Same label used for all NHs.
• Total Prefixes: 20,000 (e.g., 10k IPv4, 10k IPv6).
• Unique (Dest IP + MPLS) Tuples: 20,000 (different destination IPs, same MPLS label).
• Prefix Mapping: 1 unique prefix -> 1 unique NHG (1:1).
• Total NHs: 20,000 (20,000 NHGs × 1 NH/NHG = 20,000 total NHs).
• gRIBI Rate/Batch: Baseline (e.g., 1 ModifyRequest/sec, 200 entries/request) - QPS not the primary focus here.

• Goal: Scale across multiple VRFs with unique labels per VRF.
• Network Instances (VRFs): 1024.
• Total NHGs: 20,000 (distributed across VRFs, ~19-20 NHGs/VRF).
• NHs per NHG: 1.
• Total NHs: 20,000 (20,000 NHGs × 1 NH/NHG = 20,000 total NHs).
• MPLS Labels: 1024 unique labels (1 label assigned per VRF, consistent with #VRFs = 1024).
• Total Prefixes: 20,000 (distributed across VRFs, ~19-20 prefixes/VRF).
• Unique (Dest IP + MPLS) Tuples: 20,000 (e.g., 20 unique destination IPs reused per MPLS label/VRF).
• Prefix Mapping: Prefixes within a VRF map to NHGs using that VRF’s unique MPLS label.
• Inner IP Reuse: Required.
• gRIBI Rate/Batch: Baseline - QPS not the primary focus here.

• Goal: Similar to Profile 2, but test potentially skewed distribution of prefixes/routes per VRF/label.
• Network Instances (VRFs): 1024.
• Total NHGs: 20,000.
• NHs per NHG: 1.
• Total NHs: 20,000 (20,000 NHGs × 1 NH/NHG = 20,000 total NHs).
• MPLS Labels: 1024 unique labels (1 per VRF).
• Total Prefixes: 20,000.
• Unique (Dest IP + MPLS) Tuples: 20,000.
• Prefix Mapping: Similar to Profile 2, but the distribution of the 20k prefixes across the 1024 VRFs/labels might be intentionally uneven (e.g., some VRFs have many more prefixes than others). Exact skew pattern TBD.
• Inner IP Reuse: Required.
• gRIBI Rate/Batch: Baseline - QPS not the primary focus here.

• Goal: Test ECMP scale within a single VRF.
• Network Instances (VRFs): 1 (DEFAULT).
• Total NHGs: 2,500.
• NHs per NHG: 8 (each NH having a different destination IP).
• Total NHs: 20,000 (2,500 NHGs × 8 NHs/NHG = 20,000 total NHs, respecting the 20k NH constraint).
• MPLS Labels: 1 (consistent with #VRFs = 1). Same label used for all NHs.
• Total Prefixes: 20,000 (e.g., 10k IPv4, 10k IPv6).
• Unique (Dest IP + MPLS) Tuples: 20,000 (different destination IPs across all NHs, same MPLS label).
• Prefix Mapping: 8 unique prefixes -> 1 unique NHG (8:1 mapping, repeated 2500 times).
• gRIBI Rate/Batch: Baseline - QPS not the primary focus here.

• Goal: Test gRIBI control plane QPS scaling and impact on dataplane. Uses Profile 1 as the base state.

• Network Instances (VRFs): 1 (DEFAULT).

• Total NHGs: 20,000.

• NHs per NHG: 1.

• MPLS Labels: 1.

• Total Prefixes: 20,000.

• Unique (Dest IP + MPLS) Tuples: 20,000.

• Prefix Mapping: 1:1.

• Total NHs: 20,000 (20,000 NHGs × 1 NH/NHG = 20,000 total NHs).

• gRIBI Operations: Program/Modify the full 20k entries (1 Prefix + 1 NHG + 1 NH = 3 operations per entry = 60k operations total).

  • Target Rate: 1,000 operations/second (aiming to update the full table in maximum of 60 seconds).
  • Operation Mix: Test with 50% ADD, 50% DELETE operations during high-rate phase.

• Dataplane Validation: Ensure live traffic forwarding remains stable and correct during high-rate gRIBI operations. The primary success criterion is zero packet loss during the update phase. This validates that the DUT correctly implements a “make-before-break” update sequence, where traffic for a modified prefix is seamlessly forwarded using either the old or the new state, without being dropped.

• Program all gRIBI entries (NHs, NHGs, Prefixes) according to the profile using baseline rate/batch.
• Validate FIB_PROGRAMMED status is received from DUT for all entries.
• Verify AFT state on DUT for a sample of entries (NH, NHG, Prefix -> NHG mapping).
• Send traffic matching programmed prefixes from appropriate ingress ports.
• Verify traffic is received on egress ports with correct MPLS-over-UDP encapsulation (correct outer IPs, UDP port, MPLS label).
• Measure packet loss (target: <= 1% steady state).
• Delete all gRIBI entries.
• Verify AFT state shows entries removed.
• Verify traffic loss is 100%.

• Program all gRIBI entries across all specified VRFs according to the profile using baseline rate/batch.
• Validate FIB_PROGRAMMED status for all entries.
• Verify AFT state on DUT for a sample of entries within different VRFs.
• Send traffic matching programmed prefixes, ensuring traffic is directed to the correct VRF (e.g., via appropriate ingress interface mapping).
• Verify traffic is received with correct MPLS-over-UDP encapsulation, including the VRF-specific MPLS label.
• Measure packet loss (target: <= 1% steady state).
• Delete all gRIBI entries.
• Verify AFT state shows entries removed across VRFs.
• Verify traffic loss is 100%.

• Perform Single VRF Validation steps.
• Additionally, verify that traffic sent towards prefixes mapped to the ECMP NHG is distributed across the multiple NHs within that NHG (requires ATE support for flow analysis or DUT counter validation for NH packet/octet counters).

• Establish the baseline state (e.g., program 20k entries as per Profile 1).

• Start traffic flows matching the programmed entries. Verify baseline forwarding and low loss.

• Initiate high-rate gRIBI Modify operations (e.g., 100 ModifyRequests/sec, 10 ops/request, 50% ADD/50% DELETE mix targeting existing/new entries).

• Monitor gRIBI operation results (ACKs) for success/failure and latency.

• Continuously monitor traffic forwarding during the high-rate gRIBI phase.

  • Verify traffic uses correct encapsulation based on the programmed state.
  • Measure packet loss (target: minimal loss, allowing for brief transient loss during updates, but stable low loss overall).

• Validate FIB_PROGRAMMED status is received promptly for updates.

• Verify AFT state on DUT reflects the changes made during the high-rate phase.

• Stop high-rate programming and measure steady-state loss again.

• As an extension, investigate if the number of VRFs impacts gRIBI QPS or dataplane stability during high-rate updates. This could involve running a variation of Profile 5 using the multi-VRF setup from Profile 2 or 3 as the baseline state.

paths:
  # AFTs Next-Hop state (Verification)
  /network-instances/network-instance/afts/next-hops/next-hop/encap-headers/encap-header/state/index:
  /network-instances/network-instance/afts/next-hops/next-hop/encap-headers/encap-header/state/type:
  /network-instances/network-instance/afts/next-hops/next-hop/encap-headers/encap-header/mpls/state/mpls-label-stack:
  /network-instances/network-instance/afts/next-hops/next-hop/encap-headers/encap-header/udp-v6/state/src-ip:
  /network-instances/network-instance/afts/next-hops/next-hop/encap-headers/encap-header/udp-v6/state/dst-ip:
  /network-instances/network-instance/afts/next-hops/next-hop/encap-headers/encap-header/udp-v6/state/src-udp-port:
  /network-instances/network-instance/afts/next-hops/next-hop/encap-headers/encap-header/udp-v6/state/dst-udp-port:
  /network-instances/network-instance/afts/next-hops/next-hop/encap-headers/encap-header/udp-v6/state/ip-ttl:
  /network-instances/network-instance/afts/next-hops/next-hop/encap-headers/encap-header/udp-v6/state/dscp:
  /network-instances/network-instance/afts/next-hops/next-hop/state/counters/packets-forwarded:
  /network-instances/network-instance/afts/next-hops/next-hop/state/counters/octets-forwarded:
  /network-instances/network-instance/afts/next-hops/next-hop/state/ip-address: # NH IP
  /network-instances/network-instance/afts/next-hop-groups/next-hop-group/state/id:
  /network-instances/network-instance/afts/next-hop-groups/next-hop-group/next-hops/next-hop/state/index:
  /interfaces/interface/subinterfaces/subinterface/ipv4/neighbors/neighbor/state/link-layer-address:

  # AFTs Prefix Entry state (Verification)
  /network-instances/network-instance/afts/ipv4-unicast/ipv4-entry/state/next-hop-group:
  /network-instances/network-instance/afts/ipv6-unicast/ipv6-entry/state/next-hop-group:

rpcs:
  gnmi:
    gNMI.Set:
      union_replace: true
      replace: true
    # Primarily used for verification (Subscribe/Get)
    gNMI.Subscribe:
      on_change: true
    gNMI.Get:
  gribi:
    # Used for programming all AFT entries
    gRIBI.Modify:
    gRIBI.Flush:

• FFF